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Spec: The History of Spec World
LATEST MAASTRICHTIAN - EARLY PALEOCENE (65 - 62,000,000 bp) Across the globe, the Earth has become a grand stage for spectacular tectonic activity. Great mountain ranges are being pushed upwards accompanied by volcanic activity the likes of which have never been seen before in the Mesozoic. The grandest spectacle takes place on the Gondwanan fragment of India as it dashes itself against the Asian plate. Erupting in their full glory are the volcanoes that will create the Deccan Traps, leaving an area of 1.5 million square kilometers buried under 2 kilometers of flow basalt. This is not the only upheaval facing the world. Across the globe the oceans have been in retreat for the past few million years, exposing vast tracts of shallow seafloor. Great Britain rises from its watery prison. The two halves of North America are reunited as the Interior Seaway vanishes. The extent of the continental landmasses is dramatically enlarged. Soon it is possible to walk around the entire Northern Hemisphere without getting one's feet wet. All this activity has put life on Earth under intense stress. Great clouds of volcanic ash screen the sunlight with dire consequences for many phototrophic organisms. Whole continental shelf communities are left high and dry. Once lush island paradises are suddenly faced with continental climates that bring extremes of temperature and erratic rainfall, now often laced with sulphuric acid. In the oceans, global oceanic cooling and the draining of inland seas leads to a near total annihilation of the world's tropical reef ecosystems. Many once diverse families are eliminated or reduced to a few cosmopolitan species. Entire food chains collapse, from tiny plankton to the apex predators. The mosasaurs and ammonoids somehow manage to pull through. The graceful elasmosaurs and pliosaurs are not so fortunate. On the seafloor, once vast beds of giant inoceramid clams dwindle then vanish whilst their cousins, the rudists, are reduced to a handful of coolwater species. Although the rudists as a group will survive up until the present day, their time as the dominant reef-builders is over. Gone forever are the great shadows cast by traditional pterosaurs soaring high overhead. The pioneers of vertebrate aviation have surrendered the skies to the birds and recently evolved mammalian bats. Alas, neither of these groups will ever produce a flier that comes even close to rivalling the sheer majesty of the largest pterosaurs. However, remnants of the great beasts thrive in Australia. Life on land is also under siege. Death in different parts of the world might come from earthquakes, volcanoes, chemical contamination, fluctuating temperatures or increasing aridity. Forests wither. Embryoes die within the egg. And if that wasnít enough, the falling sea-levels unite previously isolated landmasses, allowing populations of dinosaurs to travel unhindered between the continents. Soon their wanderings bring the added burdens of introduced diseases and new competitors. Most non-avian dinosaur lineages suffer a marked drop in diversity. Across the globe, the number of dinosaur species in any given area can usually be counted on one hand. In all, an estimated 15-20% of the earth's biodiversity is lost during this time. As their struggle for survival becomes an ever-increasing nightmare, few of the animals notice the new star that has appeared in the heavens. As the weeks progress it gradually grows in size, trailing its gossamer train in its wake. Bigger and brighter it becomes until it becomes clearly visible in the daylight where the volcanic clouds do not mask the view. Then on one night the wanderer seems to lose it's resolve and grows almost imperceptibly dimmer. As the nights pass it's waning continues, smaller and smaller, until it is lost amongst the myriad of stars. The world has arrived at a crossroads and taken one path at the expense of another. For the dinosaurs, the grim struggle to live continues, oblivious to the even grimmer fate that has just been averted. THE SAD TALE OF Baropecudis cornuforns '' One of the most perplexing puzzles of Specworld's fossil record concerns the disappearance of the pachycephalosaurs. These thick-skulled ornithischians, commonly referred to as "boneheads" or "pachys", first appear in the Barremian of Europe and for the rest of the Cretaceous form a minor component of most terrestrial fossil assemblages in Asia and North America. On Spec, despite having been spared the sudden annihilation of their Arel counterparts at the K-T, the boneheads do not last very far into the Cenozoic. ''Baropecudis, informally known as the "Sz", is one of several fascinating fossil forms discovered by Clayton "Reedstilt" Bell's expeditions to Central Asia.This 2 metre long pachycephalosaur, known from several complete skeletons, is notable for the long horn found on some adult skulls. No other bonehead is known to have possessed such a horn although the rest of the anatomy suggests that the Sz (Malaysian for "unicorn") is a derived homalocephalid. Surprisingly, it seems that only the adult FEMALES possessed this horn, a conclusion based on skeletal morphology and the presence of shell fragments in the abdominal cavity of three horned individuals. Why the females should have such an lethal-looking horn is unclear. Perhaps the females were responsible for anti-predator defence whilst the males fought amongst each other for mating rights with their conventional pachy-heads. Based on the curvature of the eggshell fragments, it appears that the mother Baropecudis laid only one or two enormous eggs akin to that of an Arel kiwi. The pelvic region of the females was laterally expanded to allowthe passing of such a monstrous object which in life may have been about 25cm at it's longest and 15 cm at its widest. Importantly, the deposits from which the fossils were excavated are believed to be of either Late Paleocene or Early Eocene in age. If so, this makes it the youngest known pachycephalosaur on Spec. Elsewhere, the boneheads vanish from the fossil record midway through the Paleocene for no apparent reason, a fact made more confusing by the relative abundance of pachycephalosaur fossils in Early Paleocene sites throughout the Northern Hemisphere. Some Late Maastrichtian deposits (Like the Sandy Site of Arel's South Dakota) would seem to suggest that the pachys were doing quite well despite everything going on around them at the end of the Cretaceous. Early in the Paleocene, boneheads are relatively common throughout the Northern Hemisphere (represented by at least four genera worldwide) and are often the only non-avian dinosaurs represented in some fossil assemblages. Then, as the Paleocene progressed, something went very wrong. While other small ornithischians began to diversify, the boneheads suddenly vanished, with only Baropecudis surviving till the end of the epoch. Just what could have happened to bring about the demise of the boneheads in such a short space of time has become a hotly debated topic. The fact that they failed to radiate despite a noticeable lack of competition might suggest that the Paleocene pachycephalosaurs were somehow specialised in ways unknown to us. Their fall would seem to coincide with the diversification of other groups like the protoceratopsians which might have outcompeted them. Or perhaps their breeding habits, assuming that the other pachys laid small clutches like the Sz, left them vulnerable to nest predation. It has even been speculated that their brief success was directly tied in with the conditions of the Late Maastrichtian and earliest Paleocene which so many other species found to be detrimental. When the "bad times" ended they found themselves unable to adapt to the "good times". The fact of the matter is that we simply do not know what happened to Spec's boneheads. LATE PALEOCENE (c.63 - 57,000,000 bp) Depleted ecosystems around the world are regaining their lost biodiversity as conditions improve. Surviving pockets of forest spread outwards across the land, their growth facilitated by the dearth of herbivores. The seas once again teem with plankton allowing marine food chains to reestablish themselves. Insects fill the skies, quickly followed by the birds and early bats. Mammals and lizards scurry in the undergrowth. Maybe fewer than 100 non-avian dinosaur species worldwide made it through the K-T boundary in sufficient numbers to keep their kind in existence. A roll call of the Northern Hemisphere finds many faces missing, Gone forever are the speedy ornithomimosaurs , the bizarre alvarezsaurs (which still survive in the south) and all but a handful of the horned ceratopsians. All the northern sauropod species are extinct. Strangely, the bone-headed pachycephalosaurs seem to survive the K-T intact only to vanish before the end of the Paleocene. Biodiversity remains globally poor, most species are generalists with very large distributions. The runaway volcanism and the horrid black clouds of ash and acid have subsided. However, low sea-levels maintain extensive land-bridges between most continents, keeping regional endemism to a minimum (Europe and North American share more than two thirds of their tetrapod genera at this time) but also giving life the chance to repopulate the most remote of depleted areas. At this time Africa plus most of the Northern Hemisphere landmasses seem to form one broad biogeographical region. The dominant large plant eaters are hadrosauroid ornithopods, although only three genera are commonly represented a hadrosaurine, a lambeosaurine and, restricted to Africa and Europe, a small basal hadrosaur (Anserodromeus antiquus). Both the giant ceratopsids and sauropods are represented by one genus each, the former found throughout the region, the latter largely restricted to Africa and Europe. Large theropods include at least one tyrannosaur and a moderate-sized abelisaurid. The status of the smaller dinosaurs at this time is unclear - but the presence of hypsilophodonts, leptoceratopsians, small ankylosaurs and maniraptorans is inferred. The situation in Greater Gondwana (South America, Antarctica and Australia) is patchily understood. The sauropods apparently fared much better in this part of the world with at least 3 genera surviving. Large ornithopods are rare but at least two smaller-bodied families, ancestors of the modern Neodryosauria and Antarctornithopoda, are widespread. The alvarezsaurids are also alive while the ankylosaurs are very rare and scattered. The top predators appear to be giant maniraptoran protobirds although the more primitive abelisaurids are also in force. As the Paleocene draws to a close, the dinosaurs which made it through the K-T extinction event are well on the road to recovery and diversification. Varying conditions across the globe prod widely distributed species to form clines, then distinct races before ultimately speciating into completely new forms. Their empire may have recently been through hard times but the great beasts have survived and continue to rule the Earth. The Age of the Dinosaurs goes on... EARLY TO LATE EOCENE (c.57 - 40,000,000 bp) It is a time of plenty. The continents are altering their outlines and positions as the seafloors spread rapidly. The seas have advanced since the Paleocene, severing land-bridges and facilitating isolation and regional endemism. Global temperatures are warm, nurturing lush tropical floras as far north as Britain. In the seas, warm climate and the return of shallow inland seas put evolution into overdrive. Most modern fish families are now present while the mosasaurs undergo a major diversification event, the archetypal serpentine body shifting into everything from small eel-like river-dwellers to delphinoid pelagic forms. On land, one could be forgiven for thinking that they were back in the Cretaceous. In North America, the flat-headed hadrosaurine duckbills had branched into a number unique of endemic lineages. But these animals lived in the shadow of the immense Brontoceratops robustus, the most massive ceratopsian to have ever existed. Stalking the herds were the tyrannosaurs which have obviously hit upon a winning formula, being practically unchanged since the Cretaceous. Across the sea in Eurasia, differences between Old and New World fauna were becoming more pronounced after a long period of uniformity. Hadrosaurines and giant ceratopsids are also present, but were much less common. Here the dominant herbivores were the hollow-crested lambeosaurs followed by the smaller cousins of the ceratopsids, the hog-like protoceratopsids. The big predators were also tyrannosaurs, but they tended to be smaller and a lot more bizarre-looking than their American cousins. Evidence of other coelurosaurs is sporadic, but it is clear that this epoch was a time of diversification for both the oviraptorosaurs and the deinonychosaurs, now the only small predators left in the Northern Hemisphere. Mammals were present as small burrowing and climbing insectivores. In Europe and North Africa, there was surprise reappearance of the piscivorous spinosaurs after an absence in the fossil record for 40 million years. Where they had been for all that time is one of Specworld's many unsolved mysteries. Africa, now sliced in half by inland seas, is once again isolated and its dinosaurs are now heading off in their own evolutionary direction. Once again, the land is dominated by herds of giant duckbills, mostly the descendents of Paleocene-Asian immigrants but members of a more primitive local clade are also on the march. Sauropods also flourish as do a host of smaller, poorly understood herbivores. Africa has acquired some Asian tyrannosaurs but they face competition from a much older theropod clan, the neoceratosaurian abelisaurs. On the other side of the world, this was the final hour for the united Greater Gondwanan dinosaur-fauna, just before the terminal breakup. The last land-connection to South American has only just been severed to Antarctica, while Australia is hanging on by a thread. The sauropods reign supreme; herds of giant long-necked earthshakers are everywhere. Aside from a few duckbills, descendents of a Paleocene interchange with North America, the ornithischians are less conspicuous, but they are still diverse and abundant in the smaller herbivore guilds. Two endemic ornithopod radiations are now recognizable, the medium-sized browsing neodryosaurs and the diminutive omnivorous antarctornithopods . As in Africa, the abelisaurids are on the prowl, but here they play second fiddle to the notoraptors, a group of enigmatic giant sickle-clawed maniraptorans. The status of the dinosaur fauna of India at this time and during the folling period of extinction is presently unknown. EXTINCTION AT THE EOCENE-OLIGOCENE TRANSITION During the closing phase of the Eocene Epoch (the Priabonian) and the opening phase of the Oligocene (the Rupelian), dinosaur communities worldwide were once again plunged into crisis. Across the globe, countless species were facing extinction, both on the land and in the oceans. The direction of evolution on the Specworld was to be forever altered. The extinctions of Eocene-Oligocene transition did not take place as a single discrete event, but rather as a series of extinction pulses. The first took place close to the start of the Priabonian about 40 million years ago with three or four additional pulses taking place throughout the Eocene-Oligocene transition, the last one occurring 31 million years ago towards the end of the Rupelian. A similar phenomenon occurs in Arel's fossil record and the progression of events in both timelines show strong similarities with regards to the marine fossil record. In the oceans during the extinction pulses, those groups most seriously affected were generally tropical and inshore forms. Many foraminiferans disappear, and those that survive show a heightened amount of oxygen 18 in their tests (a phenomenon associated with a lowering in temperature). Tropical calcareous nanoplankton are decimated whilst high-latitude floras of these organisms appear at the equator. The evidence points to both a cooling of the world's oceans as well as a severe drop in global sea-levels during the final pulse of extinctions in the Oligocene. Such conditions at sea would in turn have a direct consequence for life on land. Although there is some evidence of extraterrestrial impacts during this time, it seems likely that this climatic deterioration and fluctuation was tied in with final breakup of the ancient Gondwana. Towards the end of the Eocene, Australia rifted away from its last connections with Antarctica. Cold water flowed into the widening gap, deflecting the warm currents that had previously kept the south polar climates mild. For the first time since the Paleozoic, a permanent ice cap began to form at the South Pole. With the formation of the psychrosphere, a great chilling engine was created in the southern oceans. Warm water was trapped in the south where it was cooled and forced to descend into the ocean depths before spreading back towards the equator. Each time the cool temperatures were sent towards the lower latitudes via wind, oceanic currents or upwellings, it triggered off a wave of extinctions. In the longer term, this marked the start of a profound shift in the Earth's climatic history would ultimately lead to the ice ages of the Pleistocene. LATEST EOCENE TO LATE OLIGOCENE (40,000,000 - 24,000,000 bp) The exact timing of many of the terrestrial extinctions is unclear. Most dinosaurs seemed relatively unaffected by the first extinction pulse at the start of the Priabonian, but took losses close to the Eocene-Oligocene boundary. The final pulse, accompanied by the dramatic dip in sea-levels, seems to have been the final nail in the coffin for many already struggling taxa. After millions of years of climatic seesawing, some semblance of stability had at last come to the world. The fragments of Gondwana were now fully separated. Australia and India crawled northwards, while Antarctica, now isolated in the extreme south, continued towards increasingly frigidity. The climate still supported vast tracts of lush greenery, but now there was a distinct hint of drier times to come in many parts of the world. Here, the forests were giving way to savannah woodlands where the recently evolved grasses were playing an increasingly prominent role. In many ways, the dinosaur fauna of the Oligocene was the most bizarre of the entire Cenozoic. It was a world that mixed the last survivors of relict clades with early representatives of familiar present-day families. Many of the oldtimers were giants including the Asian lambeosaur Sauropodimimus and the South American sauropod Acrotitan. However, these old survivors were outnumbered by a host of weird and wonderful newer forms. The Oligocene was the peak of protoceratopsian diversity, with the clade represented in Eurasia and North America by everything from tiny forest runners to titanic long-necked browsers. Duckbills of all shapes and sizes marched across North America and Africa, although they were not very diverse in Eurasia. Here, the most common ornithopods were the eurolophs, enigmatic creatures with no close living relatives. Strange herbivores, unrelated to anything elsewhere, also appeared South America and Australia. The carnivores seemed to also get into the spirit of weirdness. Northern tyrannosaurs sported all manner of strange cranial crests, as did the abelisauroids of South America and Africa. In Australia, a group of ornithopods called rhynchoraptors seized the top predatory niches, breaking the theropod-monopoly for the first time since the Triassic. In terms of family-level diversity, most researchers consider the Late Oligocene to mark the zenith of the Cenozoic dinosaur fauna. As the Oligocene drew to a close and the Miocene began, however, this diversity began to wane. In the oceans and throughout most of the southern landmasses, it was business as usual (aside from unusually high planktonic turnover). However, in a greater part of the northern hemisphere, the dinosaurs were vanishing, losing close to one third of their species diversity. EXTINCTION AT SPEC'S OLIGOCENE/MIOCENE TRANSITION (c. 24,000,000 - 23,000,000 bp) The solar system is a messy place, littered with rocky and icy leftovers from its coalescence. The Earth suffers chronic encounters with these wanderers, and while most are too small to be of much consequence, a few, like the monster of RL's K-T, leave their scar upon both the face of the planet and the creatures that dwell upon it. At the very end of the Oligocene, such an event seems to have occured. Close to 23 million years ago, a great flaming rock fell from the sky. It slammed into the arctic and left a steaming crater 20 km across. It was not the largest object to have crossed Earth's path, nor was the impact the only one of its time. But for life on Earth, the rock had found the worst possible place to crash into. The area surrounding the impact was undoubtably devastated immediately. Thick clouds of ejecta in the air would have stalled photosynthesis across much of the Northern Hemisphere, breaking down food chains across North America and Eurasia and leading to the starvation of millions of animals. As devastating as this catastrophe must have been, the scorching of the sky was not the most serious consequence of the collision. The blast of the impact had, after vapourising the surface sediments, encountered bedrock rich in anhydrite (calcium sulphate) and various carbonates. Great quantities of this material, some from over 1.7 km deep within the Earth, was thrown into the atmosphere where it lead to an increase in greenhouse gases and deadly falls of acid rain. For the most part, the Southern Hemisphere seemed to escape any serious damage, although the last of South America's sauropods vanished at this time. Throughout North America and Eurasia, however, the dinosaurs were in peril. In North American fossil-bearing deposits produced at that time, one often finds as few as two or three dinosaur species where once there were over twenty. On the whole, larger dinosaurs were more seriously affected than smaller ones. The last of the giant lambeosaurs along with most of the larger ceratopsians, eurolophs and neohadrosaurs vanished. Tyrannosaurs survived as a group, but lost many of their more bizarre members. The survivors were the errosaurs---small and generalised like the early cenoceratopsians and megahadrids. Without competition, these little predators quickly spread and proliferated in the Early Miocene. On both Spec and, RL the eroded scar of the 23 million year-old impact, known as the Haughton crater, sits in the high arctic of North America (75°22'N, 89°41'W). The effects of the impact on RL's Cenozoic biosphere is still being investigated and it has been implicated in a number of regional extinctions. What is certain however, is that no megafaunal extinction event of the magnitude of Spec's decimated northern dinosaur faunas occured in our native timeline. Why this would be the case when all physical aspects of the impact appear identical on both worlds is one of many issues under scientific scrutiny. One possibility concerns the lack of insulatory structures (such as fur or feathers) on most herbivorous dinosaurs. This may have made them more sensitive to such a sudden large-scale climate change compared to their mammalian RL counterparts. SPEC'S MIOCENE EPOCH (c.24,000,000 - 5,000,000 bp) The longest epoch of the Cenozoic bore witness to great changes in the geography and biota of the planet. As the wandering landmass of India finally collided with the Asian mainland, an event which spawned the highest mountains in the world, the Americas pushed westwards against the Pacific Plate, creating up the Rockies and the Andes. As Africa drew ever closer to Europe, it sounded the death knell for the ancient Tethys Sea. Cut off from neighbouring oceans, this once great ocean quickly evaporated into a vast dry salt-encrusted basin. While the Atlantic ultimately broke through the straights of Gibraltar and gave rise to the Mediterranean, the land link between Africa and Eurasia was to remain unbroken to the present day. Life in the seas was rich and varied. Giant predatory saurocetes and sharks prowled the tropics. while large swimming birds taking advantage of the rich polar waters. At several points during the Miocene, the the seas experienced sharp drops in temperature, accompanied by an expansion of the Antarctic ice sheet. However, these episodes were not severe enough to trigger anything more that mild, localised extinctions at sea or on land. Vegetation on the land was lush and vibrant. Dense forests thrived across the globe. As more water was trapped at the poles,however, open grasslands and savannah spread rapidly, bringing about the evolution of some new clades while restricting and decimating others. For life in the northern hemisphere, it was time of tremendous inter-continental migration and expansion. Africa, Eurasia, and North America were united, allowing free passage to wandering dinosaurs. At the start of the Miocene, the dominant Eurasian herbivores were the few euroloph families that had survived the Haughton impact. These natives were, however, soon locked in a losing ecological battle against successive waves of invading duckbills from neighbouring continents. Predatory dinosaurs also marched across the land bridges, the scaly African priscataurs rampaged across tropical Asia while Eurasian deinonychosaurs moved into Africa. Early paleontologists excivating in Spec's eastern Eurasiawere quite surprised to discover the scattered remains of what appeared to be a group of tiny, ant-eating therizinosaurs, with elongated tubular snouts and large digging claws. These fossils were dubbed "microsegnosaurids" and were present in the literature for years before the more detailed examination of the fossils proved that these bizzare therizinosaurs were too bizarre to be real. Recent studies of "microsegnosaurus", the first-discovered and most complete "microsegnosaurid" discovered proved that what was thought to be a single organism was, in fact, a chimera. The "ant-eating therizinosaur" was actually an amalgum of two unrelated organisms, a small therizinosaur possibly related to today's Seculasauridae and an alvarezsaur, the last known from the Eurasian continent. The three other species of "microsegnosaurid" (all of which based upon scattered elements) proved to be either therizinosaur of alvarezsaur material, lumped together with "microsegnosaurus" because of similarities with one part or another of its patch-work skeleton. While Africa and the North experienced a mixing of faunas, the rest of the world was a study in isolation. Australia and South America remained worlds apart from any other landmass, surrounded by oceans on all sides. Both continents were enjoying a boom in ornithopod evolution that gave rise to a host weird endemic forms, from giant pseudosauropods to vicious rhynchoraptors. Australia began to lose much of its ancient rainforests as it charged northwards into drier latitudes. In Regards to the Enigmatic Case of Both Mirificranium coronatus ''and Stegocephalosaurus baiamei'' Both on HE and Spec the continent of Australia is known to host archaic, surprising and just plain weird forms of life. But to uncover some of the most perplexing creatures, you have to dig deep, as a group of specpaleontologists discovered. While hoping to uncover the ancestor of the rhynchoraptorans, they uncovered a startling specimen that didn't seem to make sense at all: a partial skull with fragmentary postrcania that looked like it could have belonged to a strange pachycephalosaur with a crown of spikes and two prominent fangs. The animal was named Mirificranium coronatus, meaning confusing crowned skull. Such a find was hard swallow for several reasons. First of all, there were no known pachycephalosaur remains found in Australia prior to this, and secondly the age seemed too far removed from the last known Specworld pachycephalosaurs. Mirificranium ''could be dated to the Ogliocene with reasonable accuracy, while the last of the pachycephalosaurs were supposed to have become extinct early Eocene. The tale got another twist when another, more complete skull was found from early Miocene deposits. This animal, ''Stegocephalosaurus baiamei(meaning creator god Baiame's roofheaded reptile) had a less flamboyant skull covered by a flat bony pad. Though there were enough similarities in the skull morphology to classify the animal as a marginocephalian, it didn't seem to belong to a pachycephalosaur after all. Instead it had a lot in common with the most basal ceratopsians! An ulna is known from HE Australia that has been tentatively assigned to a neoceratopsian (possibly Leptoceratops), which has lead to some speculation that neoceratopsians may be of Gondwanan origin. Mirificranium coronatus was however the first ceratopsian to show up in the Australian fossil record, so if there is any connection between it and the Early Cretaceous ulna, there remains a question about where the Australian ceratopians were hiding all this time. The Mirificranium postcrania also hints that the body of the animal was probably not that of the typical neoceratopsian, but rather like that of the more basal ceratopians. If a recently discovered partial postcrania from Early Miocene turns out to belong to Stegocephalosaurus, ''then the stegocephalosaurs were most likely at least habitual bipeds. There is still much more we don't know about stegocephalosaurs. We can only guess that they used their bony heads in intraspecific combat as pachycephalosaurs may have done in their time, but the purpose of the fangs is unclear. Another unanswered question is their fate. While they seem so rare in the fossil record that it is too early to make assumptions about when exactly they disappeared, they did not make it to the holocene. Their extinction is indeed a great shame, as from live stegocephalosaurs we might have learned a great deal about the evolution of marginocephalians both in our world as in spec. SPEC'S PLIOCENE EPOCH (c.5,000,000 - 1,700,000 b.p.) The geography of the Pliocene Specworld looked quite similar to the present-day map. As North and South Ameirca finally met, the isthmus of Panama rose from the sea, separating the tropical Atlantic from the Pacific and ending South America's long isolation. The Mediterranean was fully formed, but was barred from the Indian Ocean by the Sinai peninsula, which joined Africa and Eurasia. A permanent polar icecap had started to form at the Arctic, shifting the warm Gulf Stream as cool currents flowed down the Labradore coast. Temperatures on land and in the sea continued to cool. Many kinds of marine invertebrates vanished, unable to adapt to the changing temperatures, but were quickly replaced by more modern forms. The productive cool waters at the poles soon played host to a crowd of newly evolved animals taking advantage of their expanded habitat. Swimming birds radiated further and grew increasingly large. Enormous filter-feeding cephalopods harvested the clouds of krill. In warmer waters, new species of lizard-whales terrorised the oceans. On land, the vegetation was shifting in response to these cooler, drier conditions. While trees still dominated the uplands, in the mid-continental belts, they were giving way to open grasslands. Low-lying areas once covered in green forests and woodlands were now transformed into endless seas of golden grass. The rise of the grasslands lead to the loss of many ancient browsing herbivores. The armoured ankylosaurs, already uncommon since the Oligocene, declined to a handful of species in America and Australia. The last of the eurolophs were gone, while only a single genus of high-browsing sauropod remained in Africa. As some groups faded with the vanishing forests others rose to meet the evolutionary challenge. Throughout Africa and Asia, vast of herds of hoofed ungulapedes were on the march, these weird duckbills soon radiated into an incredible variety of forms. Cooler northern latitudes witnessed herbivorous niches becoming increasingly dominated by two of the most unlikely of candidates - the therizinosaurian theropods and the paraselenodont mammals. In North America, the neohadrosaur duckbills continued their monopoly of the large herbivore guilds. Also making their presence felt were the frill-necked ceratopsians. These dinosaurs had been absent from North America since the end of the Oligocene and their recent arrival from Asia heralded the return of giant horned herds to the continent. Biogeographically, the most important event of the Pliocene was the linking of the two Americas. Much of the unique South American megafauna vanished in the face of North American immigrants. The northern dinosaurs had dealt with climatic change and faunal interchange with Asia throughout the Cenozoic, thus were full of competitive vigour. Their southern counterparts, on the other hand, have lived on a more stable, isolated world for millions of years and in most cases fare poorly against the invaders. Soon, duckbills and ceratopsians had displaced many unique South American ornithopod families, while tyrannosaurs and hesperonychids had replaced the abelisaurs and endemic notoraptors. Of the large southern herbivores, only the giant pseudosauropods held their own. However, the migrations were not one-way, as neotropical viriosaurs and marsupials flourished in the north. The only major landmasses still completely isolated were Antarctica and Australia. The former was now virtually lifeless, but the latter boasted a staggering display of weird endemics. The thick forests that once covered most of the island continent were now restricted to the margins, giving way to open woodlands and savannah. One lineage of herbivores, the euclasaurs, had undergone an explosive evolutionary radiation akin to that of the Old World ungulapedes. Hunting these odd herbivores were their predatory rhynchoraptor cousins. SPEC'S QUATERNARY PERIOD (c.1,700,000 - 0 b.p) A little less than 2 million years ago, the Earth entered what can only be described as a climatic rollercoaster, a time which marked the end of the Neogene Period and the start of the Quaternary Period. Thus began a series of drastic cooling phases for the planet, the famous Ice Ages. In RL, the Quaternary is divided into two epochs - the Pleistocene and the Holocene (the time from the last glaciation up until the present day). Although these units are sometimes used on Spec for purposes of convenience, it should be noted that: a) the biotic changes that have characterised the Holocene on RL are far less profound on Spec (see below) b) evidence collected on both worlds suggests that this current phase of mild climate is little more than a short interglacial period and that the Specworld is heading towards yet another round of glaciation. On RL the activities of industrialised humanity appears to be reversing this situation. From about 1.7 million to 11,000 years ago, the world experienced at least four major glacial episodes. Great sheets of ice spread out from the Arctic, covering much of North America and Europe. Increased glaciation also occured in the southern hemisphere although to a much lesser extent. At its peak, about 44 million sq km of the planet's surface was ice-bound. With so much water locked away, sea-levels fell by over 100 metres, resulting in the devastation of local marine faunas and the creation of several land-bridges, including those across the Bering Strait, the English Channel, the Torres Strait, and the Sea of Japan. After a time, the ice would retreat and the world would be given the brief respite of an interglacial that saw the return of milder conditions. The effect of the Ice Ages, both on the landscape and the creatures that inhabited it, was profound. The flow of the glaciers carved great valleys in the Earth, while accumulating boulder clays and moraines. Strongs winds near the ice sheets carried fine-grained dust to distant lands, resulting in thick loess deposits in Africa, central Asia, and midwestern North America. With regards to the vegetation, the coming of the Ice Age heralded the arrival of vast areas tundra in the north, providing a rich feeding ground for cold-adapted grazers, such as polar therizinosaurs and large paraselenodont mammals. In the lower latitudes, some areas acquired lush woodlands while others faced increasing aridity. When the ice retreated, temperate forests returned to the high-latitudes, accompanied by herds of hadrosaurs. Each phase of glaciation and interglacial proved to be of benefit to some organsisms at the expense of others. The ranges of some animals expanded while other were reduced to scattered populations only to have the situation reversed when the extent of the ice shifted. In all physical aspects, the progression of the Ice Ages of Spec appears to have been identical to that of RL. However, with regards to life on the planet, there is one startling contrast. The conclusion of the last Ice Age on RL broadly coincided with the extinction of many large terrestrial animals - mammoths, giant deer, ground sloths, sabre-tooth cats, etc. As far as can be determined, such a phenomenon did not occur on Spec. 11,000 years ago, the ranges of many tundra-dwelling dinosaurs, such as the arctotitan, were certainly greatly reduced, often accompanied by a reduction in body-size. Some areas also experienced localised extinctions, particularly North America, which lost its ceratopsians as great areas of woodland were converted to open praries. But on the whole, probably over 90% of all of Specworld's Ice Age megafaunal genera are still alive and well. This evidence points the finger of blame firmly at humanity for the extinction of the great beasts of our own home time-line. Spec, never subjected to the curse of the killer ape, remains the abode of giants. Examples of the Extinct Fauna Based On Their Respective Time Period. '''Cretaceous ' * Gigantala cranitus * Baropecudis cornufrons '' '''Eocene' * Eohadrus excelsius * Megacaudia nameni * Brontoceratops robustus '' * ''Eobrachiceratops * Patriopokemus mordax '' * ''Phobotyrannus robustus '' * ''Phobotyrannus gracilis '' * ''Balaenanguis primitivus * Gigantops dominus * Pisciraptor nauticus '' * ''Arbroraptor mongoliensis Oligocene * Formicornithoides * Sauropodimimus * Gryphorynchys robustus * Lycovenator paraxenos * Paramegahadrus vetus * Megabeluasaurus magnacephalus * Procurvihadrus specensis * Megaloceratops gracilis * Protoerrosaurus borealis Miocene * Archaeopristrix * Tricerolophus chooi * Wabulasaurus steveirwini * Formicornithoides europeanus * Microsegnosaurus myrmicophagus * Teratodon maturus * Mirificranium coronatus * Stegocephalosaurus baiamei * Titanotarsus * Pikodon maximus * Massosuchus * Archaeopristrix * Therizinonychus * Microsegnosaurus * Teratodon * Eomucrodontosaurus * Bellasaurus * Pygmihadrus Pliocene * Struthiopes indigena * Carnofalx bestialis * Nanodon jonesi * Rhinolophosaurus imperator * Microsegnosaurus * Carnofalx * Megabeluasaurus magnacephalus * Hipposaurus * Probactyrannus * Projugalceratops * Saltotyrannus nanus Plestiocene * Macropokemus robustus * Monoceratops acutus Category:Spec Dinosauria Category:Extinct Category:Asia Category:North America Category:Australia Category:South America Category:Europe Category:Africa Category:Pachycephalosaurs Category:Mammals Category:Hadrosauroids Category:Ceratopsians Category:Tyrannosaurs Category:Theropods Category:Ornithopods